[[FIX]] Honor globals config in JavaScript API

Prior to this commit, the `globals` configuration value was not
considered for invocations of the JavaScript API. Ensure that option is
consistently interpreted according to the project documentation. Ensure
that globals defined by the more specific `predef` option of the API
take precedence over globals defined using this configuration option.

src/jshint.js

@@ -5345,18 +5345,21 @@ var JSHINT = (function() {
     }
 
     if (o) {
-      each(o.predef || null, function(item) {
-        var slice, prop;
-
-        if (item[0] === "-") {
-          slice = item.slice(1);
-          JSHINT.blacklist[slice] = slice;
-          // remove from predefined if there
-          delete predefined[slice];
-        } else {
-          prop = Object.getOwnPropertyDescriptor(o.predef, item);
-          predefined[item] = prop ? prop.value : false;
-        }
+
+      each([o.predef, o.globals], function(dict) {
+        each(dict, function(item) {
+          var slice, prop;
+
+          if (item[0] === "-") {
+            slice = item.slice(1);
+            JSHINT.blacklist[slice] = slice;
+            // remove from predefined if there
+            delete predefined[slice];
+          } else {
+            prop = Object.getOwnPropertyDescriptor(dict, item);
+            predefined[item] = prop ? prop.value : false;
+          }
+        });
       });
 
       each(o.exported || null, function(item) {

tests/unit/core.js

@@ -38,6 +38,33 @@ exports.testCustomGlobals = function (test) {
     .addError(3, 1, "Read only.")
     .test(code, { es3: true, unused: true, predef: { foo: false }});
 
+  JSHINT("x = null;", { undef: true, globals: { x: true } });
+
+  test.ok(!JSHINT.data().errors);
+
+  JSHINT("x = null;", { undef: true, globals: { x: false } });
+
+  test.equal(JSHINT.data().errors.length, 1);
+
+  JSHINT("parseInt('');", { undef: true, globals: { "-parseInt": true } });
+
+  test.equal(JSHINT.data().errors.length, 1);
+
+  JSHINT('x = null;', { undef: true, globals: { x: false } }, { x: true });
+
+  test.ok(
+    !JSHINT.data().errors,
+    "`predef` parameter takes precedence over `globals` option"
+  );
+
+  JSHINT("x = null;", { undef: true, globals: { x: true } }, { x: false });
+
+  test.equal(
+    JSHINT.data().errors.length,
+    1,
+    "`predef` parameter takes precedence over `globals` option"
+  );
+
   test.done();
 };